The best-known pleorama was a 19th-century moving panorama entertainment where the viewers sat in a rocking boat while panoramic views on painted canvas rolled past.
Architect Carl Ferdinand Langhans introduced a pleorama in Breslau in 1831 with scenes of the Bay of Naples on both sides of 24 "voyagers" sitting in a wooden boat floating in a pool of water.
The Swiss writer Bernard Comment, among others, has pointed out the similarities between Langhans' pleorama and the ambitious mareorama at the 1900 Paris Exhibition.
In 1850s Finland the name pleorama was given to shows which presented historic scenes and panoramic views using glass, but posters for these do not mention anything resembling Langhans' boat concept.
The pleo- part here is understood to come from a Greek word meaning 'float' which applies to Langhans' boat in water idea.